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The Digital Nautical Chart (DNC®) is a vector based digital product that is designed to provide the mariner with an up-to-date seamless database of the world. Digital Nautical Chart portrays selected significant navigational features in a format suitable for computerized navigation and Geographic Information System (GIS) applications. Digital Nautical Chart is produced in the standard Vector Product Format (VPF) allowing for modeling real world features in digital geographic databases. The database uses a table based georelational data model and supports GIS applications such as mission planning, command and control, and situational awareness. The Digital Nautical Chart database consist of 29 Digital Nautical Chart geographic regions providing a complete worldwide footprint containing over 5,000 charts of varying scales. Digital Nautical Chart is a comprehensive, world-wide chart database for ship navigation, and a component of other complex NGA VPF products such as littoral warfare and tactical ocean data.

Scale:   The Digital Nautical Chart contains four library categories based on scale and purpose of the source charts including Harbor, Approach, Coastal and General charts, from largest to smallest scale, respectively. In addition, there is a single Browse library that acts as an index.

Accuracy: Absolute horizontal and vertical accuracy are expressed at a circular/linear errors at 90% probability. NGA strives to compile hard copy nautical charts with the most accurate depth information available. NGA charts are compiled from a variety of sources with varying accuracies. Information regarding the source data used for each chart comprising the Digital Nautical Chart can be found in the Data Quality coverage of each library.

Content:  The Digital Nautical Chart database is based on and developed from the feature content of NGA and National Ocean Service hard copy charts. The features depicted are thematically organized into 12 layers or coverages including: Cultural Landmarks, Earth Cover, Environment, Hydrography, Inland Waterways, Land Cover, Limits, Aids to Navigation, Obstructions, Port Facilities, Relief, and Data Quality.

Key Info Shown:  Marine geographic information is displayed in a digital vector or "smart" format. This allows the user to display only the information desired for safe navigation as an example.

Mission Area Application:  This product contains vector data and feature content for thematically layered, relationally structured set of databases to support electronic chart display systems for the US Navy, US Coast Guard, government agencies and government/US military sponsored contractors. Public sale of Digital Nautical Chart in US waters is anticipated in the near future.